Can use SocNetV to analyze a virtual "social network" ? Yes you can. For instance, you could analyze social interactions (i.e. mentions) between "friends" in that virtual network. Apparently, SocNetV cannot grab their link/connections data on its own (forget the built-in web crawler; it cannot get and parse private data), but if you can extract the data for yourself and transform them into a proper GraphML format, then SocNetV will happily load and visualize the virtual social network so that you can analyze its properties. This seems to be the case with Dolphin social network software, an open source platform for social networks.
The guys behind the project kindly informed me that they are about to use SocNetV as an "intelligence" source for Dolphin-site operators. Dolphin and its mobile-friendly sibling Trident support social connections, conversations, locations and other social-graphs related data types, which can be used by SocNetV depending on operator needs. For example, "if an air-line company launches a social network for clients, they could use SocNetV to analyze connections between friends within network, trends of their discussions and posts, and then use that to plan which routes would be in demand and when. Later they could create special offers to relevant segments of the network and advertise it within their site". Seems an interesting use for SocNetV. Kudos to boonex guys!